It will also evaluate the cardiovascular events of the large outcome trial, the first occurrence of any of the following clinically significant outcomes: Death [ Time Frame: 2 years ] [ Designated as safety issue: Yes ]

New development of any of the following echo changes clinically indicated or done for the trial: Segmental wall motion abnormalities [ Time Frame: 2 year and end of study ] [ Designated as safety issue: No ]

Ventricular aneurysm [ Time Frame: 2 year and end of study ] [ Designated as safety issue: No ]

Reduction in left ventricular (LV) ejection fraction > 5% [ Time Frame: 2 year and end of study ] [ Designated as safety issue: No ]

Increase in left ventricular diastolic dysfunction (LVDD) > 5.0 mm compared with baseline [ Time Frame: 2 year and end of study ] [ Designated as safety issue: No ]

To determine the efficacy of benznidazole in patients with Chronic Chagas heart disease based on a 50% reduction in both qualitative and quantitative PCR. [ Time Frame: 3 Years ] [ Designated as safety issue: Yes ]

1. New development of any of the following echo changes clinically indicated or done for the trial: segmental wall motion abnormalities, ventricular aneurysm, reduction in LV ejection fraction > 5%; increase in LVDD > 5.0 mm compared with baseline

Evaluate if benznidazole, an antiparasite drug, given at a dose calculated as 5mg/kg/day for 60 days, now administered as a fixed daily dose of 300mg during 40 to 80 days of treatment - period adjusted according to the patient's body weight to a total minimum dose of 12g (corresponding to 40kg) and a total maximum dose of 24g (corresponding to 80kg) - reduces morbidity and mortality in patients with Chronic Chagas' Cardiomyopathy (CCC).

The BENEFIT study is being conducted by the Population Health Research Institute (in Hamilton, Canada) and the Institute Dante Pazzanese de Cardiologia (Sao Paulo, Brazil) together with an independent Steering Committee.

Detailed Description

A randomized double-blind controlled clinical trial investigating the role of benznidazole in patients with chronic Chagas' heart disease.

Chagas disease has 3 phases: acute, undetermined and chronic phases. There are no clinical trials up to date that have investigated the use of antiparasitic drugs in patients that are in the chronic phase.

This study will evaluate the efficacy and safety of benznidazole (an antiparasitic drug) in patients with chronic Chagas' heart disease. Evaluate if benznidazole, an antiparasite drug, given at a dose calculated as 5mg/kg/day for 60 days, now administered as a fixed daily dose of 300mg during 40 to 80 days of treatment - period adjusted according to the patient's body weight to a total minimum dose of 12g (corresponding to 40kg) and a total maximum dose of 24g (corresponding to 80kg) - reduces morbidity and mortality in patients with Chronic Chagas' Cardiomyopathy (CCC). It will be developed in 54 study centres in Argentina, Bolivia,Brazil,Colombia and El Salvador - countries with high incidence of Chagas Disease.

The Pilot study is evaluating if benznidazole is effective in producing parasitic cure (PCR negativization or reducing parasitic load) in chronic Chagas Disease as well as assessing the feasibility of conducting a large trial in chronic Chagas Disease in South America.

a dose calculated as 5mg/kg/day for 60 days, now administered as a fixed daily dose of 300mg during 40 to 80 days of treatment - period adjusted according to the patient's body weight to a total minimum dose of 12g (corresponding to 40kg) and a total maximum dose of 24g (corresponding to 80kg)